Both ScreenFlow (Mac-only) and Camtasia (Mac/Win) support subtitling. Both are excellent screencast applications but I prefer ScreenFlow because it creates MPEG-4 files whereas Camtasia requires Flash for subtitles and that pretty much rules out mobile.

If these screencastsare made with some other, less expensive apps, I suggest using free, open source apps. There are many but I prefer Jubler for creating subtitles and Subler for installing them in MPEG-4 files. These are Mac apps.

In creating accessible online and blended courses, one of the challenges we
are dealing with is making sure faculty created videos (narrated
PowerPoints, screencasts, etc.) are accessible. I would love to hear how
others are handling this. Do you recommend/require that these videos be
closed captioned? If so, who is responsible for creating the closed
captions? Do you have staff on campus that do this or is it the faculty
member’s responsibility? Or do you use a service? Can you recommend any
software that helps someone easily create closed captions or a service that
can provide this?